A NASA astronaut preparing for a grueling eight-month stint in orbit reveals a plan to test for extraterrestrial life.

The main focus of the trip is to study the effects of long-term spaceflight on the body, but the test is also a side mission.

NASA administrator Jared Isaacman says declassified UAP files show real unexplained phenomena but no alien bodies or crashed ships have been found.

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The Pentagon has released a fresh batch of declassified UFO-related files containing decades of unexplained sightings reported by astronauts, military personnel and surveillance systems. The ...